Sunk on 15 May 1944 in the Strait of Gibraltar north of Tangier, in position 35.54N, 05.45W, by depth charges from the British patrol vessel HMS Kilmarnock, the British A/S trawler HMS Blackfly and two US Catalina aircraft (VP-63 USN/P-1 & P-14). 54 dead (all hands lost).

Attacks on this boat and other events

19 May 1943The target of the depth chage attack on 19 May 1943 SE of Cape Farewell, Greenland in position 55.09N, 35.18W by a British B-24 Liberator bomber (Sqdn. 120/T), formerly credited with sinking U-954, was in fact U-731, which escaped unscathed. (Sources: 1991-10-01, FDS/NHB)

4 Oct 1943Six men were wounded, including the commander, when a British Hudson bomber (Sqdn 269/S) attacked. The boat was able to continue the patrol despite being damaged.

12 Oct 1943The boat was attacked by three Avenger aircraft from USS Card. U-731 had another air attack one week previously in which six men, including the commander, were wounded and the boat was damaged.